Poles for use in dance exercise, or pole dancing, have become very popular in recent years. Such poles extend between floor and ceiling and generally comprise at least two tubes connected together in series according to the height required. The poles may be erected and dismantled by coupling or decoupling the tubes. To facilitate coupling and decoupling, joints are provided between the tubes. There are presently two forms of joint used, screw joints and insert joints, both of which suffer from drawbacks.
Screw joints are expensive to manufacture, since they require an insert to be welded into the end of a tube and a finishing operation. During use, when a pole becomes warm, the tubes and joint can expand so that the screw threads become locked together and it is difficult to unscrew the joint after use of the pole. Alternatively, the screw joint can be unscrewed during use by anti-clockwise rotation if it is not sufficiently tight.
Insert joints must be smaller than the tubes into which they are inserted, accordingly they are prone to movement within the tubes, which results in flexing of the pole and/or relative rotation of the tubes during use. Furthermore, when a pole becomes warm during use the insert can expand causing the tubes to become locked together and difficult to separate.
Coupling devices having a body that radially expands are also known for joining tubes together, for example from UK patent application no. 0713866.2. However, such coupling devices can be difficult to operate as during operation moving parts can become misaligned thereby preventing the body from expanding correctly. This provides the problem that a user may believe that the coupling device is properly engaged with the tubes, for example because a screw of the moving parts become difficult to turn, when in fact this in not the case and can result in a potential hazard for the user.
The present invention sets out to provide an improved coupling device for a pole dancing pole that overcomes the problems of the prior art.